1. Technical Field
The present invention relates to a method for manufacturing metal nanoparticles and in particular, to a method for manufacturing metal nanoparticles which can easily control size of the metal nanoparticles and make metal nanoparticles' dispersibility higher without using a polymer dispersing agent under a non-polar solvent.
2. Description of the Related Art
There are chemical manufacturing method, mechanical manufacturing method and electrical manufacturing method in producing metal nanoparticles.
It is difficult to synthesize nanoparticles of high purity and uniform size due to the entrainment of impurity in mechanical process where mechanical power is used in grinding. As to electrical manufacturing method employing electrolysis, the production efficiency is low since the throughput time is long and yield of particles produced is low.
Meantime, there are two major chemical methods of producing metal nanoparticles, namely the vapor method and the colloid method. However, since the vapor method which uses plasma or gas evaporation requires highly expensive equipment, the colloid method by which particles of uniform size can be synthesized at low cost is generally used.
The method of manufacturing metal nanoparticles by the colloid method is separated into an aqueous method and a non-aqueous method. In the aqueous method, since a particle distribution is relatively big and a size of the synthesized particles is basically tens of nano-size, an oxidation speed is slow. Therefore there is a problem that synthesizing metal nanoparticles in high concentration is difficult, even though it is no need to special treat to prevent an oxidation.
The other hand, in the non-aqueous method, compared to the aqueous method, particles of uniform size can-be synthesized and synthesizing tens of nano-size of metal particles is possible. However, because the size of nanoparticles is generally just tens of nano-size, size growth of dispersed nanoparticles is limited when metal nanoparticles are synthesized with the non-aqueous method.
For those reasons, it is necessary to study about new method which can control the size of nanoparticles and can propose higher dispersibility in the non-aqueous method.